Semi-automatic firearm magazine



FIG. 1 is a top plan view of a semi-automatic firearm magazine, showing my new design;

FIG. 2 is a bottom view thereof;

FIG. 3 is a left elevation view thereof;

FIG. 4 is a right elevation view thereof;

FIG. 5 is a front elevation view thereof; and,

FIG. 6 is a back elevation view thereof.

The broken line showing of portions of the semi-automatic firearm magazine is included for the purpose of illustrating environment and forms no part of the claimed design. 

I claim, the ornamental design for a semi-automatic firearm magazine, as shown and described. 